The overall purpose of the present study is an understanding of the chemical architecture of the brain and the relationships between its protein and lipid components. Primary emphasis is placed on the chemistry of myelin proteins. During the coming year the major effort will be directed towards the long range goal of determining the amino acid sequence of proteolipid protein from bovine brain white matter (myelin proteolipid). We plan to 1) continue to purify and sequence the peptides which we have obtained by tryptic digestion of performic acid oxidized and non-oxidized proteolipid preparations. 2) develop procedures for the isolation of cyanogen bromide peptides from the proteolipid apoprotein; 3) develop procedures for using high pressure liquid chromatography for the purification of peptides, particularly hydrophobic peptides, which are difficult to separate by conventional column chromatography. An additional line of investigation will be to characterize the carbonic anhydrase which we have purified from myelin, to compare it with carbonic anhydrase from other brain fractions and to study its relationship with other myelin components. These studies address fundamental problems related to myelin and should contribute to an understanding of the normal process of myelination and the abnormalities which occur in demyelinating diseases including multiple sclerosis and diseases of genetic and environmental origin. The carbonic anhydrase studies may have implications for understanding seizure mechanisms. BIBLIOGRAPHIC REFERENCES: Chan, D.S. and Lees, M.D. Acid soluble tryptic peptides from bovine white matter proteolipids. Trans. Am. Soc. Neurochem. Vol 8, p. 57 (1977). Sapirstein. V.S. and Lees, M.B. Characterization of Plasma Membrane Proteolipid from Rat Kidney. Fed. Proc. 36: 361 (1977).